Latch tripping mechanism



June 2, 1953 H. w. SANFORD 2,640,508

LATCH TRIPPING MECHANISM Original Filed Jgn. 20, 1943 3 Sheets-Sheet l June 2, 1953 H. w. SANFORD men mmuc uscumsu Origihal Filed Jan. 20, 1943 3 Shoots-Sheet 2 June 2, 1953 H. w. SANFORD LATCH TRIPPING MECHANISM Original Filed Jan. 20, 1943 3 Sheets-Sheet 3 INVENTOR my 14. Sanford Patented June 2, 1953 ATCH TRIPPING MECHANISM Hugh W. Sanford, Knoxville, Tenn., assignor to The Sanford Investment Company, Wilmington, Del., a corporation of Delaware Original application January 20, 1943, Serial No. 473,013, now Patent No.-2,441,978, dated May 25, 1948. Divided and this application July 22, 1947, Serial No. 7 62,637

9 Claims. (Cl. 214-58) This application is a division of my prior application for Latch Tripping Mechanisms,Serial No. 473,013, filed January 20, 1943, now Patent No. 2,441,978, granted May 25, 1948.

This invention relates to latch tripping mechanisms, and more particularly for releasing the latches of drop bottom mine cars or other conveyors, of the type set forth in my prior application on Door Latch Mechanism, Serial No.

432,341, filed February 25, 1942, now Patent No.

2,399,708, granted May 7, 1946.

In conveyors of the character used for hauling coal and other loose lading by means of cars or the like, particularly such as employ mine cars, provision is made for the automatic dumping of such conveyors by releasing the drop bottom doors when the conveyor reaches the bin or other point of discharge. It has been customary and desirable for a series of drop bottom doors to be interconnected for successive dropping in 1-2-3 order from front to rear of the car when the car reaches the point of dumping. f This has been accomplished usually by supporting a free edge of a forward door upon a hinged'edge of the next rearward door in such manner that the opening of the latter will release automatically the forward door for dropping. The rearmost door of the car has its free edge supported by latch means adapted to be released when the car reaches the point of dumping.

. Such automatic cars as generally used hereto fore have required latch bar mechanism located outside the car for controlling the dropping of the doors. Such latch bar mechanism has been objectionable and expensive.

I have set forth in my'prior application on Door Latch Mechanism, Serial No. 432,341, Patent No. 2,399,708, improved latch mechanisms for controlling the release of the doors.

The object of this invention is to improve the construction of the tripping mechanism for the door latches, to facilitate the release. of the latches byv mechanism having improved characteristics, while enclosing the latches in protected positions on the car.

I have shown the invention in several modified forms in the accompanying drawings, in which: 1 Fig; 1 is a side elevation of tripping mecha-' nism, with the car shown somewhat diagrammatically;

Fig. 2 is a top plan view of the tripping mechanism;' a

- Fig. 3 is an end elevation thereof; and -Fig. 4 is 'a'side'elevation of a modified form of tripping mechanism, having electrical actuating means.

The invention is shown as applied to a dropbottom mine car adapted for the conveying of coal or other loose lading from a receivingpoint to a pit or other point of discharge. The mine car is shown generally of the type set forth, for instance, in my prior Patent No. 2,001,471, granted May 14, 1935, representing a four-wheel mine car having three drop bottom doors, adapted to travel on a track formed by a pair of rails designated generallyR. v

The general structure of the car comprises side and end walls I and 2, respectively, the side walls I rising from a pair of oppositely'disposed side sills 3 connected together at the ends of the car by means of combined end-sills and bumpers designated generally 4. The side and end sills 3 and 4 constitute the frame structure of the car for supporting the lading body of the car.

The car is supported on' wheels 5 and axlesfi,

connected with the side sills 3. The flaring sides I of the body are cut away to receive the wheels, which are deeply inserted therein beneath wheel hood coverings 8.

The car is shown as of the character provided with three drop bottom doors adapted for dis charge in 1-2-3 order from front to rear of the car, only the rear door 12a being shown in Fig. 1,' In isv slidably and pivotally' and said door mounted on a hinge rod [4, with the extreme forward edge of said door projecting laterally from the hinge rod and arranged to supportthe free edge of the next forward door.

Thus upon release of the rear door it may drop; sufficient to drag and move bodily rearward, thereby releasing the free edge of the middle door which will likewise move downward and rearward releasing the free edge of the forward door. This occurs usually just before the car reaches the bin and permits dropping of the forward door for discharge of the lading as soon as room enough is provided in the bin therebeneath, the other, doors dropping in succession during forward movement of the car over the bin, in 1-2-3 order from front to rear of the car.

After dumping in passing over the;bin, the doors are adapted to be closed by the usual door closing rails located in the track, said doors hav; ing indentation .15 to ride thereon, which successively swing them into their closed positions The doors may be pushed forward into tightly I engaged supportingv positions by wedge blocksv having upwardly and forwardly inclined front faces in position for engagement by'lugs attached to the free edge of the rearward door I20. and projecting therefrom, as set forth more fully in my prior United States Patent No. 2,001,471, granted May 14, 1935.

As shown in Figs. 1 to 3, provision is made for latching the free edge of the rearward door 12 for holding thereby the doors in their closed positions, retaining the lading in the car until the latching means is released for dumping. For this purpose latches We are provided adjacent the rear end of the car, spaced transversely on opposite sides of the center of the car, and pivotally supported by a shaft 19,.extending transversely thereof on which said latches are fixed for swinging movement.

Each of the latches I8a is mounted on the car substantially as described in my Patents Nos. 2,399,708 and 2,441,978, for supporting the free edge of the rearward door I2a by engagement with trunnions Zla thereon. The latches are adapted to. be engaged by tripping means mounted in the trackway separate and apart from the latch mechanism, to release the latches when desired.

In Figs. 1 to 3, I have shown one form of triparm 65 having a head 86 at the upper end thereof in position for engaging an edge of the latch I80. when the tripping arm is raised to the position shown in Fig. 1. The tripping arm 65 is pivoted at 61 on a bracket 68 mounted beneath the track on a suitable support. A counterweight 69 is mounted on the rearward end of the tripping arm 65 tending to reduce the effective weight of the tripping arm and the amount of power required to lift it, but without preventing this arm from falling promptly when the lifting motion imparted thereto has been removed.

One side of the tripping arm 65 has a shoulder T in position to be engaged by a wedge H which is formed at the forward end of an elongated member 72. The wedge member 12 is supported by rollers 13 mounted in a track (4 for longitudinal movement therein. The roller mounting for the wedge H insures the movement of said wedge in the vertical plane of the tripping arm 65 and with a minimum of friction.

The roller guide M has a slot 15 in the under side thereof through which extends the upturned forward end of a connecting bar 16 which is pivoted to the wedge member 12 at ll. The forward end of the connecting bar 76' has pressure applying means connected therewith tending to move the same toward the left in Fig. 1. This means is shown as a counterweight T8 carried byone end of a cable 19, the opposite end of which cable is connected with the connecting bar 16', while the cable extends therefrom over a guide sheave 80. Any other suitable pressure applying means may be substituted for the counterweight, such as a spring.

The forward end portion of the connecting bar 16 has a composite actuating arm pivoted thereto at 8i. The actuating arm is composed of upper and lower sections 82 and 83 arranged in overlapping relation and in a common upright transverse plane. The links 83 constituting the lower section embrace the endportion of the connecting bar 76. The upper arm section 82 is adapted to be engaged by the lug 41a.

fixed to the under side of the sill of the car.

4 Links 82a are arranged at the lower end of the arm section 82, substantially forming a continuation thereof.

The arm section 82 is journaled loosely on a cross shaft 84 for freedom of turning movement relative thereto, which shaft is mounted in bearings 85 suitably supported beneath the track; The links 82a and arm sections 83 are fixedly secured to said shaft 34. The upper arm section 82 has secured thereto a laterally extending bracket 86 from the outer end of which is suspended a counterweight 81, as a suitable pressure applying means tending to turn said arm section 82 in a counter-clockwise direction in Fig. 1. The links 8201. have an abutmentv 88 in position to engage a shoulder portion at the lower end of the arm section 82 to limit the counter-clockwise direction of movement of the arm section 82 relative to the shaft 84, while the.

rounded adjacent portion of the section 82 will permit freedom of turning movement of the latter in a clockwise direction in Fig. 1, relative to the section 83.

In the operation of this form, the actuating arm 8.2 would stand normally substantially in a vertical position in the path of movement of the lug did. When engaged by this lug and moved to the position shown in Fig. 1, the actuating arm composed of the sections 82 and '83 would move the connecting bar 16 lengthwise and thereby force the wedge H under the shoulder 10 of the tripping arm 65. This raises the tripping arm to the position shown where its head 66 engages the forward face of the latch [8a, forcibly moving the latter from beneath the door trunnion 21a. and releasing the door for dropping. This is a positive releasing motion of the latch, caused by a wedging action, but the latter is applied to the tripping arm rather than to the latch as described above.

When the car has moved forward so that the lug 47a has passed over the upper end of the actuating arm composed of the sections. 82 and 83, the pressure means T8 pulling forward on the connecting bar TB, withdraws the wedge 11 from lifting engagement with the shoulder 10 the tripping arm is toward the latch and sill.

Since the counterweight 8! acts in opposition to the counterweight 78, the latter should be made sufiiciently heavier to overcome the resistance of the former to the left-hand movement of the bar it. The counterweight 18 must be made heavy enough to move the bar 16 to the left whenever the occasion demands, namely, where the arm section 82 is out of engagement with the lug a.

If the car sill carrying the. lugfla should be. lowered as aresult of wear on the wheels or otherwise, the movement of the connecting bar t6 would be increased. To prevent the tripping arm 65 from being raised too high in that event. the wedging member '12 is so formed that the: shoulder Ill-moves onto a fiat portion of the memher at the top of the wedge when the tripping member has been lifted to the desired extent. Thus, any additional movement of the connecting aec eos bar 16 to the right, as a result of a lowering of the car body, will not result in any additional raising motion of the tripping arm 65 above that shown in Fig. 1.

As described, in normal operation, the actuating arm 82-83 functions as a unit with both of the upper and lower parts thereof moving together in a counter-clockwise direction. This is due to the pressure applied by' the counterweight 81 holding the arm section 82 in the relative position illustrated with the lower end of said section bearing against the abutment 88. If the car should pass over the tripping mechanism in reverse direction, toward the right in Fig. 1, the rearward end of the lug 41a would engage the upper end of the arm section 82 and rotate the latter about the shaft 84 against the pressure of the counterweight 81, but without moving the section 83. Therefore, there would be no resulting movement of the tripping mechanism including arm 65.

. Although Figs. 1 and 2 show one set of latches and tripping mechanism, it is obvious that latches may be provided at both sides of the car, if desired, as pointed out above. It is possible to use two complete sets of tripping mechanism for actuating the respective latches, one on each side of the center line of the car, and each operating the adjacent latch IBa without reference to the other tripping mechanism. It is also possible to have on set of tripping mechanism for operating lifting wedges on opposite sides of the center line of the car, as will be obvious from this description and the drawings.

In the modification shown in Fig. 4, electrical tripping mechanism is provided for releasing the door latches, instead of the mechanical tripping mechanism set forth above. The electrical actuating means is claimed in a separate application.

In the form shown in Fig. 4, a tripping arm 95, substantially like the tripping arm 65' set forth above in the form shown in Figs. 1 to 3, has a head 96 in position to be moved into engagement with a forward face of the door supporting latch IBb which normally supports the free edge of the door I2b by means of a trunnion 2 lb, as described above. The tripping arm 95 is pivotally supported at 91 on a bracket 98, and has a counterweight '99 on the opposite end thereof from the head 96. This counterweight 99 reduces the amount of power required to raise the tripping arm 95, but does not prevent it from falling promptly when released.

The tripping arm 95 has a shoulder I in position for engagement by a wedge IOI carried at the forward end of a member I02, slidably mounted upon rollers I03 within a guide member I04. This wedge and its mounting correspond substantially with similar parts described above in connection with Fig. l. The guide I04 has a slot I in the under side thereof through which an arm I06 projects, which arm is rigidly formed on the wedge member I 02. The arm I06 is pivotally connected at I01 with a plunger I08 of an electrical solenoid I09. A coiled spring H0 is sleeved over the plunger I08 and has a bearing engagement therewith at its outer end at III, tending to move the plunger in an outer direction relative to the solenoid I09.

The solenoid is controlled by a switch which is actuated by a shoe H2 in position for engagement with a lug 41b secured to the under face of the sidesill of the car as described. The shoe H2 is secured to a sleeve H3 slidably connected at H4 with a rocker member H5 which is pivotally 6 supported at H6. A coiled spring H1 is housed within the sleeve I I3 and tends to extend the shoe H2 relative to the rocker member H5. The

rocker member H5 is free to turn in a clockwise direction in Fig. 4 about the pivot I I6, but has its movement in the opposite direction limited by an arm II-8 adapted to engage a rigid stop H9 mounted in a fixed position beneath the track. A spring I20 is connected between the rocker member I I5 and a stationary anchor I2 I, tending to restore the rocker member and the shoe I I2 to a central position, as shown, if moved out of said position.

The sleeve I I3 has an arm I22 projecting laterally therefrom and supporting a plunger I23 slidably mounted therein through an insulating bushing I24. A coiled spring I25 tends to move the plunger I23 in one direction. The free end of the plunger I23 carries a contact I26 in position to engage a contact I21 secured to the rocker member H5 but insulated therefrom. The contact I21 is connected through a wire I 28 with the solenoid I09. The contact I26 and opposite side of the solenoid coil may be connected with a track circuit or other source of electrical supply through suitable connections as shown, adapted to energize the solenoid upon the closing of the switch I26-I21.

When the shoe H2 is engaged by the lug 41b and depressed, this will close the contacts I26, I21, sufiiciently to energize the solenoid I09. When the solenoid is thus energized, the plunger I08 is moved to the right in Fig. 4, thereby moving the wedge I 0I to its dotted line position, pressing upward on the shoulder I00, and raising the tripping arm 95 to the dotted line position illustrated. This moves the head 96 in position to engage the forward face of the latch I8b upon further forward movement of the car to release the door for dropping. As soon as the lug 41b passes over the shoe H2, the latter is raised by the spring H1 disengaging the contacts I26, I21, which causes deenergizing of the solenoid coil I09. This allows the spring I I0 to move the wedge IOI back to the full line position, and allowing the tripping arm 95 to be lowered out of the path of the latch I81), and the end sill of the car; for dumping of the doors in the manner described above.

It will be noted that the position of the shoe H2 is centralized in a vertical position by the action of the spring I20, so that it tends to return to its vertical position when out of engagement with the lug 41b. Normally, the lug merely depresses the shoe in said vertical position, but when the car moves over the dumping bin and the tripping mechanism in a reverse direction (toward the right in Fig. 4), the shoe II2 will be rotated toward the right by the engagement of the lug 41b. The switch will rotate with the shoe since it is carried by the rocker member H5 and will not be closed by this rotary movement because of the lack of movement of the shoe I I2 and its sleeve I I3 relative to the rocker member I I5. Thus the solenoid I09 will not be energized to raise the tripping arm 95. After the car thus passes over the tripping mechanism in the reverse direction described, the spring I20 will return the shoe I I2 to its vertical position, where it is held by the stop H9.

I As described above, one or more latches may be used for supporting the free edge of the door, and if desired, the tripping arm may be provided for each latch. One solenoid could be used, if desired, to operate several tripping arms which correspond with the respective 1atches, or sepa rate solenoids provided for the respective tripping arms, all of which may be controlled from a single switch or shoe.

While the invention has been illustrated and described in certain embodiments, it is recognized that modifications and changes may be made therein without departing from the inven' tion, except as specified in the claims.

I claim:

1. In conveying mechanism, the combination with a trackway, a dumping vehicle mounted on the traokway and including a frame structure having a drop bottom dumping door, and latch means for holding the door closed and movable to release said door for dropping, of tripping mechanism mounted at the trackway for upward movement relative thereto in position to actuate the latch means, said tripping mechanism including a tripping arm mounted for upward swinging movement to a position for engaging and releasing the latch means and for lowering movement from said engaging position, relative to the vehicle in a direction lengthwise of the dumping vehicle toward the front thereof during movement of the vehicle along the trackway, and wedging means arranged for engagement with said tripping arm and moving the same to an engaging position in a direction upwardly and rearwardly of the vehicle.

2. In conveying mechanism, the combination with a trackway, a dumping vehicle mounted on the trackway and including a frame structure having a drop bottom dumping door, and latch means for holding the door closed and movable to release said door for dropping, of tripping mechanism mounted at the trackway for upward movement relative thereto in position to actuate the latch means, said tripping mechanism including a tripping arm mounted for upward swinging movement to a position for engaging and releasing the latch means and for lowering movement from said engaging position, relative to the vehicle in a direction lengthwise. of the dumping vehicle toward the. front thereof during movement of the vehicle along the trackway, wedging means for actuating said tripping arm and moving the same to an engaging position in a direction upwardly and rearwardly of the vehicle, and means connected with the dumping vehicle for actuating the wedging means to move the tripping arm to an engaging position.

3. In conveyin mechanism, the combination with a trackway, a dumping vehicle mounted on the trackway and including a frame structure having a drop bottom dumping door, and latch means for holding the door closed and movable to release said door for dropping, of tripping mechanism mounted at the trackway for upward movement relative thereto in position to actuate the latch means, said tripping mechanism including an actuating arm mounted for upward swinging movement to a position for engaging and releasing the latch means and for lowering movement from said engaging position, said tripping arm being constructed and arranged for lowering movement relative to the vehicle in a direction lengthwise of the dumping vehicle toward the front thereof during movement of the vehiole along the traclrway, said tripping arm having a shoulder thereon, a wedge member in position for engaging said shoulder for raising said-tripping arm to a predetermined elevated position, guide means supporting said wedge member, and means actuated in response to movement of the dumping vehicle for operating said wedge member relative to the tripping arm.

4. In conveying mechanism, the combination with a trackway, a dumping vehicle mounted on the trackway and including a frame structure having a drop bottom dumping door, and latch means for holding the door closed and movable to release said door for dropping, of tripping,

mechanism mounted at the trackway and including a tripping member mounted for upward movement relative thereto in position to actuate the latch means, said tripping'mechanism including means for applyin a wedging action to raise the tripping member to actuate the latch means.

5. In conveying mechanism, the combination with a trackway a dumping vehicle mounted on the trackway and including a, frame structure having a drop bottom dumpingdoor, and latch means for holding the door closed and movable to releasesaid door for dropping, of tripping mechanism mounted at the trackway and including a tripping member mounted for upward movement relative thereto in position to actuate the latch means, said tripping mechanism including means for applying a wedging action to raise the ,tripping member to actuate the latch means, and means connected with the dumping vehicle and actuated by the movement of said vehicle for actuating the wedging means.

6. In conveying mechanism, the combination with a trackway, a dumping vehicle mounted on the trackway and including a frame structure and a bottom dumping door, and latch means for holding the door closed and movable to release said door for dropping, of tripping mechanism including a tripping member for actuating the latch means to release the door for dropping, said tripping mechanism including wedging means acting on the tripping member to raise said member to a tripping position, said wedging means being mounted in the traclrway in position such that the closed door' of the vehicle passes directly over said wedging means.

'7. In conveying mechanism, the combination of a trackway adapted to receive thereon a dumping conveyance for movement along the traokway and having a drop bottom door with latch means for holding the door closed and. movable to release the door for dropping, tripping mechanism including means mounted at the trackway for movement into operative relation with the latch means to release said latch means, said tripping mechanism including a tripping arm mounted for upward swinging movement to a latch release position and for lower-- ing movement from said release position, and wedging means arranged to apply a raising movement to said tripping arm and moving the same to latch release position. i 8. In conveying mechanism, the combination of a trackway adapted to receive thereon a dumping conveyance for movement along the track-- way and having a drop bottom door with latch means for holding the door closed and movable to release the door for dropping, tripping mechanism including means mounted at'the trackway for movement into operative relation with the latch means to release said latch means, said tripping mechanism including a tripping arm' mounted for upward swinging movement to a latch release position and for lowering movement from said release position, Wedging means? arranged to apply a raising movement to said tripping arm and moving the same to latch release position, and means actuated by movement of the conveyance to a predetermined position on the trackway for causing said actuation of the wedging means.

9. Latch tripping mechanism for a conveyance having a'drop bottom door and latch means for holding the door closed and movable to release the door for, dropping, said tripping mechanism being adapted to be mounted in the trackway and comprising a tripping member separate from the latch means and mounted for upward movement to a position for engagement by the latch means as the conveyance moves over the tripping mechanism, and means for applying a wedging action to the tripping member to release the latch.

HUGH w. SALNFORD.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,129,200 Jones Feb. 23, 1915 2,399,708 Sanford May 7, 1946 2,441,978 Sanford May 25, 1948 2,487,447 Kepner Nov. 8, 1949 

